I just finished listening to the audiobook of Sex at Dawn by Christopher Ryan and Cacilda Jethá. It’s a nonfiction analysis of the science of how human sexuality evolved. Mainly, it takes aim at the evolutionary psychologists that have presented us with a competitive model of monogamy and cheating, where men evolved to try to impregnate as many women as possible without commitment, and women evolved to select only those mates who could be coerced into committing. They point, instead, to a tribal culture where sex was free and open, used not for a “pair bond” but rather as a bond for the entire tribal band. Competition, in their view, takes place at fertilization (i.e. whose sperm will fertilize the egg) rather than by restricted matings.

It’s a fascinating book, and so chock full of useful information I won’t bother to summarize all of it here. Instead, you should read it. Or listen to it, as I did. I think you’ll find it quite convincing.

The important takeaways for me as an erotica author are manifold. Among many other things, this book explains why more women read erotica than men. It explains why MFM menage is more popular than FMF.

Sperm competition is one of the most important ideas in this book. The basic idea is that a woman’s body is designed to make fertilization difficult, so that only the fittest sperm make it to the egg. Biochemistry, the woman’s immune system, even the shape of her cervix are all designed to weed out all but a tiny fraction of sperm. This means that in evolutionary terms, it is advantageous for her to have sex with as many men as possible, in order to make that competition as fierce as possible. That explains why a woman (generally) still wants sex after she’s had an orgasm, more than a typical man would. This would seem to me, to explain why MFM menage is so popular; it synchs up well with that fundamental drive.

Sperm competition also explains why women can stay aroused for long periods of time, in spite of orgasm. To me, this is related to the greater demand for longer erotic work like novellas and novels among women. For a long time I had thought that this was simply sexism, a greater tolerance for such interests in women than in men, but I can see now that view was flawed. The difference isn’t cultural, it’s biological. Or at least, it could be.

Another book that’s been on my mind is Perv: The Sexual Deviant in All of Us by Jesse Bering. This one talks about the nature of sexual paraphilias and how they come about; it appears that your average male’s sexual preferences are set during early adolescence and persist strongly for the rest of his life, whereas your average female’s are more malleable. This is referred to briefly in Sex at Dawn, as well. Again, there’s a lot more going on in this book than I can summarize here; I recommend it to anyone interested in writing books that hook deep into the reader’s psyche.

To my mind, this causes the interests of male readers to become tightly focused; they want particular body types, activities, or themes presented, the same ones over and over. They discover an author or website that focuses on what they want, and they stick with it, as long as it keeps feeding their particular interests. Women, on the other hand, being more flexible, can find lots of things sexy; this explains why more women write erotica, and why there’s more variety in erotica marketed to them.

These influences may have been presenting some obstacles to my career, or at least my ignorance of these influences hasn’t been helping me any. I’ll be keeping this new information in mind as I go forward.